The National Security Agency vacuumed up more than 151 million records about Americans’ phone calls last year via a new system that Congress created to end the agency’s once-secret program that collected domestic calling records in bulk, a report disclosed Tuesday.

Although the number is large on its face, it nonetheless represents a massive reduction from the amount of information the agency gathered previously. Under the old system, it collected potentially “billions of records per day,” according to a 2014 study.

During his final year in office, President Obama's team significantly expanded efforts to search National Security Agency intercepts for information about Americans, distributing thousands of intelligence reports across government with the unredacted names of U.S. residents during the midst of a divisive 2016 presidential election.

In all, government officials conducted 30,355 searches in 2016 seeking information about Americans in NSA intercept metadata, which include telephone numbers and email addresses. The activity amounted to a 27.5 percent increase over the prior year and more than triple the 9,500 such searches that occurred in 2013, the first year such data was kept.

Information accidentally collected by the NSA overseas about Americans was subsequently searched and disseminated after President Obama loosened privacy protections to make such sharing easier in 2011 in the name of national security.

The government in 2016 scoured the actual contents of NSA intercepted calls and emails for 5,288 Americans, an increase of 13 percent over the prior year and a massive spike from the 198 names searched in 2013.

The searches ultimately resulted in 3,134 NSA intelligence reports with unredacted U.S. names being distributed across government in 2016, and another 3,354 reports in 2015. About half the time, U.S. identities were unredacted in the original reports while the other half were unmasked after the fact by special request of Obama administration officials.

A top lawyer for the American Civil Liberties Union, which has long raised concerns about the NSA’s ability to spy on Americans, said the rise in searches is a troubling pattern that should concern members of both political parties because it has occurred with little oversight from the courts or Congress.